Pub Date : 2015-12-03DOI: 10.1109/IWOW.2015.7342263
Milica I. Petkovic, G. Djordjevic
In this paper, novel analytical expression for the symbol error probability (SEP) of free-space optical (FSO) system employing subcarrier intensity modulation (SIM) with M-ary Phase-Shift Keying (MPSK) are derived, based on the Fourier series method (FSM). The irradiance fluctuations of the received signal are modeled by the K distribution convenient in strong atmospheric turbulence conditions. The hardware imperfections of PSK demodulator are taken into account, which are presented through the phase noise modeled by Tikhonov distribution. Numerical results are presented and confirmed by Monte Carlo simulations. The numerical results illustrate the effects of atmospheric turbulence strength and phase noise on SEP performance. The existence of hardware imperfections, presented through phase noise, degrades the FSO system performance to a large extent.
{"title":"SEP analysis of FSO system employing SIM-MPSK with noisy phase reference","authors":"Milica I. Petkovic, G. Djordjevic","doi":"10.1109/IWOW.2015.7342263","DOIUrl":"https://doi.org/10.1109/IWOW.2015.7342263","url":null,"abstract":"In this paper, novel analytical expression for the symbol error probability (SEP) of free-space optical (FSO) system employing subcarrier intensity modulation (SIM) with M-ary Phase-Shift Keying (MPSK) are derived, based on the Fourier series method (FSM). The irradiance fluctuations of the received signal are modeled by the K distribution convenient in strong atmospheric turbulence conditions. The hardware imperfections of PSK demodulator are taken into account, which are presented through the phase noise modeled by Tikhonov distribution. Numerical results are presented and confirmed by Monte Carlo simulations. The numerical results illustrate the effects of atmospheric turbulence strength and phase noise on SEP performance. The existence of hardware imperfections, presented through phase noise, degrades the FSO system performance to a large extent.","PeriodicalId":247164,"journal":{"name":"2015 4th International Workshop on Optical Wireless Communications (IWOW)","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123918134","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-12-03DOI: 10.1109/IWOW.2015.7342271
Hossein Kazemi, M. Uysal, F. Touati, H. Haas
In this paper, five scenarios are considered for the realization of a multi-hop hybrid free-space optical/radio frequency (FSO/RF) communication system with decode-and-forward (DF) relaying, and analytical outage probability expressions are derived. The scenarios have a different number of FSO and RF links. The aim is to identify an optimum scenario to effectively improve the end-to-end reliability of the multi-hop hybrid FSO/RF system. Outage performance is investigated for the scenarios under various weather conditions through numerical examples. It is identified that for a given link distance the end-to-end outage probability is minimized when using a hybrid FSO/RF link between every two successive nodes of the multi-hop system, and this requires the maximum number of FSO and RF links to be deployed.
{"title":"Outage performance of multi-hop hybrid FSO/RF communication systems","authors":"Hossein Kazemi, M. Uysal, F. Touati, H. Haas","doi":"10.1109/IWOW.2015.7342271","DOIUrl":"https://doi.org/10.1109/IWOW.2015.7342271","url":null,"abstract":"In this paper, five scenarios are considered for the realization of a multi-hop hybrid free-space optical/radio frequency (FSO/RF) communication system with decode-and-forward (DF) relaying, and analytical outage probability expressions are derived. The scenarios have a different number of FSO and RF links. The aim is to identify an optimum scenario to effectively improve the end-to-end reliability of the multi-hop hybrid FSO/RF system. Outage performance is investigated for the scenarios under various weather conditions through numerical examples. It is identified that for a given link distance the end-to-end outage probability is minimized when using a hybrid FSO/RF link between every two successive nodes of the multi-hop system, and this requires the maximum number of FSO and RF links to be deployed.","PeriodicalId":247164,"journal":{"name":"2015 4th International Workshop on Optical Wireless Communications (IWOW)","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129287526","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-12-03DOI: 10.1109/IWOW.2015.7342275
M. Kashef, M. Abdallah, K. Qaraqe
In this paper, we consider a cooperative visible light communication (VLC) system in which multiple access points (APs) cooperate while transmitting data to a number of associated mobile terminals (MTs). The optimal transmission power control requires information about the exact locations of the MTs and hence a large amount of information needs to be processed at the controller and needs to be transferred from the APs to the controller. In this paper, we consider the system performance in the cases where the controller employs limited available information about the MTs. We consider a system in which the APs employ optical orthogonal frequency division multiplexing (OOFDM) with power control. A centralized controller determines the data electrical power based on the available information about the MTs. We consider three levels of information which are (i) the exact locations of the MTs, (ii) the exact numbers of MTs associated with the APs, and (iii) the average numbers of MTs possibly connected to the APs. Moreover, we consider the cases in which the controller optimizes the transmission powers based on various utility functions including maximizing the summation of the achieved rates of the MTs and maximizing the minimum achieved rate of any of the MTs. The numerical results show the effect of various system parameters on the achieved utility function including the average number of MTs, the APs and MTs locations, and the required illumination powers of the APs.
{"title":"Cooperative OFDM-based multi-user visible light communication systems with limited information","authors":"M. Kashef, M. Abdallah, K. Qaraqe","doi":"10.1109/IWOW.2015.7342275","DOIUrl":"https://doi.org/10.1109/IWOW.2015.7342275","url":null,"abstract":"In this paper, we consider a cooperative visible light communication (VLC) system in which multiple access points (APs) cooperate while transmitting data to a number of associated mobile terminals (MTs). The optimal transmission power control requires information about the exact locations of the MTs and hence a large amount of information needs to be processed at the controller and needs to be transferred from the APs to the controller. In this paper, we consider the system performance in the cases where the controller employs limited available information about the MTs. We consider a system in which the APs employ optical orthogonal frequency division multiplexing (OOFDM) with power control. A centralized controller determines the data electrical power based on the available information about the MTs. We consider three levels of information which are (i) the exact locations of the MTs, (ii) the exact numbers of MTs associated with the APs, and (iii) the average numbers of MTs possibly connected to the APs. Moreover, we consider the cases in which the controller optimizes the transmission powers based on various utility functions including maximizing the summation of the achieved rates of the MTs and maximizing the minimum achieved rate of any of the MTs. The numerical results show the effect of various system parameters on the achieved utility function including the average number of MTs, the APs and MTs locations, and the required illumination powers of the APs.","PeriodicalId":247164,"journal":{"name":"2015 4th International Workshop on Optical Wireless Communications (IWOW)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133868287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-12-03DOI: 10.1109/IWOW.2015.7342277
Carlos Ribeiro, M. Figueiredo, L. N. Alves
This paper reports the implementation and performance results of a real-time Visible Light Communication platform. The platform uses a high-level software abstraction architecture where the algorithms are developed and tested in MATLAB, using a modular architecture. With this modular approach it is very easy to add/remove blocks, making it amenable to collaboration with other groups with interest in this field, offering a real-time test bed to evaluate the performance of different modules, algorithms and optical front-ends, which is currently not available. The physical layer is based on DCO-OFDM and is implemented in a Xilinx Virtex-6 FPGA. We explore the optical front-end out-of-band bandwidth to transmit, showing the usefulness of adopting OFDM-based modulations schemes for VLC. Our system transmits at 2m over an indoor free space channel with 12MHz bandwidth, with more than 23dB gain difference, using QPSK, thus achieving 24Mbit/s with a BER smaller than the usual 3.8×10-3 limit.
{"title":"A real-time platform for collaborative research on Visible Light Communication","authors":"Carlos Ribeiro, M. Figueiredo, L. N. Alves","doi":"10.1109/IWOW.2015.7342277","DOIUrl":"https://doi.org/10.1109/IWOW.2015.7342277","url":null,"abstract":"This paper reports the implementation and performance results of a real-time Visible Light Communication platform. The platform uses a high-level software abstraction architecture where the algorithms are developed and tested in MATLAB, using a modular architecture. With this modular approach it is very easy to add/remove blocks, making it amenable to collaboration with other groups with interest in this field, offering a real-time test bed to evaluate the performance of different modules, algorithms and optical front-ends, which is currently not available. The physical layer is based on DCO-OFDM and is implemented in a Xilinx Virtex-6 FPGA. We explore the optical front-end out-of-band bandwidth to transmit, showing the usefulness of adopting OFDM-based modulations schemes for VLC. Our system transmits at 2m over an indoor free space channel with 12MHz bandwidth, with more than 23dB gain difference, using QPSK, thus achieving 24Mbit/s with a BER smaller than the usual 3.8×10-3 limit.","PeriodicalId":247164,"journal":{"name":"2015 4th International Workshop on Optical Wireless Communications (IWOW)","volume":"138 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116346497","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-12-03DOI: 10.1109/IWOW.2015.7342270
G. Mehrpoor, M. Safari, B. Schmauss
In this paper, the use of optical beams carrying orbital angular momentum (OAM) is proposed to provide spatial diversity gains for free space optical communication links degraded by atmospheric turbulence. We show that transmitted beams carrying sufficiently separated OAM modes experience highly uncorrelated turbulence effects. Furthermore, the outage probability analysis confirms that spatial diversity gain is achievable using the proposed technique without requiring the deployment of multiple apertures which is necessary for traditional spatial diversity schemes.
{"title":"Free space optical communication with spatial diversity based on orbital angular momentum of light","authors":"G. Mehrpoor, M. Safari, B. Schmauss","doi":"10.1109/IWOW.2015.7342270","DOIUrl":"https://doi.org/10.1109/IWOW.2015.7342270","url":null,"abstract":"In this paper, the use of optical beams carrying orbital angular momentum (OAM) is proposed to provide spatial diversity gains for free space optical communication links degraded by atmospheric turbulence. We show that transmitted beams carrying sufficiently separated OAM modes experience highly uncorrelated turbulence effects. Furthermore, the outage probability analysis confirms that spatial diversity gain is achievable using the proposed technique without requiring the deployment of multiple apertures which is necessary for traditional spatial diversity schemes.","PeriodicalId":247164,"journal":{"name":"2015 4th International Workshop on Optical Wireless Communications (IWOW)","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114488760","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-12-03DOI: 10.1109/IWOW.2015.7342273
Hanaa Marshoud, Diana W. Dawoud, V. M. Kapinas, G. Karagiannidis, S. Muhaidat, B. Sharif
This paper investigates the performance of different precoding schemes for a multi-user MIMO VLC system with channel estimation errors, an assumption that is commonly neglected in the literature. In particular, dirty paper coding, channel inversion, and block diagonalization, are considered for interference mitigation under imperfect channel state information. The impact of the variation of the beam angles of the transmitters and the field of view (FOV) of the receivers on the system performance is also examined. Simulation results reveal that, dirty paper coding provides the best performance under perfect channel state information (CSI). However, under imperfect CSI, suboptimal linear precoding schemes will give better performance. Furthermore, tuning the transmitting angles and the FOVs can significantly improve the system performance.
{"title":"MU-MIMO precoding for VLC with imperfect CSI","authors":"Hanaa Marshoud, Diana W. Dawoud, V. M. Kapinas, G. Karagiannidis, S. Muhaidat, B. Sharif","doi":"10.1109/IWOW.2015.7342273","DOIUrl":"https://doi.org/10.1109/IWOW.2015.7342273","url":null,"abstract":"This paper investigates the performance of different precoding schemes for a multi-user MIMO VLC system with channel estimation errors, an assumption that is commonly neglected in the literature. In particular, dirty paper coding, channel inversion, and block diagonalization, are considered for interference mitigation under imperfect channel state information. The impact of the variation of the beam angles of the transmitters and the field of view (FOV) of the receivers on the system performance is also examined. Simulation results reveal that, dirty paper coding provides the best performance under perfect channel state information (CSI). However, under imperfect CSI, suboptimal linear precoding schemes will give better performance. Furthermore, tuning the transmitting angles and the FOVs can significantly improve the system performance.","PeriodicalId":247164,"journal":{"name":"2015 4th International Workshop on Optical Wireless Communications (IWOW)","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124736921","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-12-03DOI: 10.1109/IWOW.2015.7342256
E. Başar, E. Panayirci
In this paper, we propose optical orthogonal frequency division multiplexing with index modulation (O-OFDM-IM) for visible light communications (VLC) systems employing light emitting diodes (LEDs) and photodetectors (PDs). The proposed scheme uses the indices of the active subcarriers of an optical OFDM system to transmit additional information bits. In the proposed scheme, the bipolar signals are asymmetrically clipped or DC biased and a log-likelihood ratio (LLR) calculation based detector is used to determine the indices of the active subcarriers. Our computer simulations show that the O-OFDM-IM achieves better error peformance compared to classical optical OFDM schemes.
{"title":"Optical OFDM with index modulation for visible light communications","authors":"E. Başar, E. Panayirci","doi":"10.1109/IWOW.2015.7342256","DOIUrl":"https://doi.org/10.1109/IWOW.2015.7342256","url":null,"abstract":"In this paper, we propose optical orthogonal frequency division multiplexing with index modulation (O-OFDM-IM) for visible light communications (VLC) systems employing light emitting diodes (LEDs) and photodetectors (PDs). The proposed scheme uses the indices of the active subcarriers of an optical OFDM system to transmit additional information bits. In the proposed scheme, the bipolar signals are asymmetrically clipped or DC biased and a log-likelihood ratio (LLR) calculation based detector is used to determine the indices of the active subcarriers. Our computer simulations show that the O-OFDM-IM achieves better error peformance compared to classical optical OFDM schemes.","PeriodicalId":247164,"journal":{"name":"2015 4th International Workshop on Optical Wireless Communications (IWOW)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131167978","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-12-03DOI: 10.1109/IWOW.2015.7342267
S. Nazhan, Zabih Ghassemlooy, K. Busawon, Joaquin Perez
Vertical-cavity surface-emitting laser (VCSEL) devices are being used in both optical fibre and optical wireless communications. In this paper, the influence of variable polarization angle θp of optical feedback (OF) with the modulation signal on the relative intensity noise (RIN) of VCSEL is experimentally investigated. The RIN characteristic is presented with and without the modulation signal under rotated θp of the OF. A minimum RIN of -156 dB/Hz with OF at dominant mode is achieved over the entirely range of θp. However, the RIN level is degraded to -139 dB/Hz under modulation signal in presence of OF.
{"title":"Polarization RIN of VCSEL subject to modulation signal with variable polarization angle of optical feedback","authors":"S. Nazhan, Zabih Ghassemlooy, K. Busawon, Joaquin Perez","doi":"10.1109/IWOW.2015.7342267","DOIUrl":"https://doi.org/10.1109/IWOW.2015.7342267","url":null,"abstract":"Vertical-cavity surface-emitting laser (VCSEL) devices are being used in both optical fibre and optical wireless communications. In this paper, the influence of variable polarization angle θp of optical feedback (OF) with the modulation signal on the relative intensity noise (RIN) of VCSEL is experimentally investigated. The RIN characteristic is presented with and without the modulation signal under rotated θp of the OF. A minimum RIN of -156 dB/Hz with OF at dominant mode is achieved over the entirely range of θp. However, the RIN level is degraded to -139 dB/Hz under modulation signal in presence of OF.","PeriodicalId":247164,"journal":{"name":"2015 4th International Workshop on Optical Wireless Communications (IWOW)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129713710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-12-03DOI: 10.1109/IWOW.2015.7342264
S. Enayati, H. Saeedi, N. Mokari
In this paper, we analyze the problem of power allocation with the objective of maximizing the throughput for hybrid free-space optical/radio-frequency (FSO/RF) communication systems. Such systems consist of a free space optical link as well as an RF link. We consider both soft switching (SS) and hard switching (HS) schemes. In the former, at any time slot only one of the links is active while in the latter, both links simultaneously transmit data and the available power is divided between the two links. It is shown that for a given visibility, the obtained spectral efficiency is always greater than that of HS. The superiority of the SS scheme over the HS scheme is so significant such that the SS scheme outperforms the HS scheme for a visibility as bad as fives times lower than that of the HS case.
{"title":"Throughput maximization in hybrid FSO/RF communication systems","authors":"S. Enayati, H. Saeedi, N. Mokari","doi":"10.1109/IWOW.2015.7342264","DOIUrl":"https://doi.org/10.1109/IWOW.2015.7342264","url":null,"abstract":"In this paper, we analyze the problem of power allocation with the objective of maximizing the throughput for hybrid free-space optical/radio-frequency (FSO/RF) communication systems. Such systems consist of a free space optical link as well as an RF link. We consider both soft switching (SS) and hard switching (HS) schemes. In the former, at any time slot only one of the links is active while in the latter, both links simultaneously transmit data and the available power is divided between the two links. It is shown that for a given visibility, the obtained spectral efficiency is always greater than that of HS. The superiority of the SS scheme over the HS scheme is so significant such that the SS scheme outperforms the HS scheme for a visibility as bad as fives times lower than that of the HS case.","PeriodicalId":247164,"journal":{"name":"2015 4th International Workshop on Optical Wireless Communications (IWOW)","volume":"94 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126228869","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-12-03DOI: 10.1109/IWOW.2015.7342257
Shihe Long, M. Khalighi, M. Wolf, Zabih Ghassemlooy, S. Bourennane
Carrier-less amplitude and phase (CAP) modulation has recently been considered as an alternative to optical orthogonal-frequency-division-multiplexing (O-OFDM) in visible light communication (VLC) systems. The main advantages of CAP over O-OFDM are its lower implementation complexity at the transmitter side and its lower peak-to-average power ratio. Here, we consider CAP modulation where matched filtering and equalization at the receiver are performed in the frequency domain, resulting in reduced system complexity. Through numerical results we investigate the performance of this transmission scheme and, in particular, study the impact of the roll-off factor and the length of the pulse shaping filters.
{"title":"Performance of carrier-less amplitude and phase modulation with frequency domain equalization for indoor visible light communications","authors":"Shihe Long, M. Khalighi, M. Wolf, Zabih Ghassemlooy, S. Bourennane","doi":"10.1109/IWOW.2015.7342257","DOIUrl":"https://doi.org/10.1109/IWOW.2015.7342257","url":null,"abstract":"Carrier-less amplitude and phase (CAP) modulation has recently been considered as an alternative to optical orthogonal-frequency-division-multiplexing (O-OFDM) in visible light communication (VLC) systems. The main advantages of CAP over O-OFDM are its lower implementation complexity at the transmitter side and its lower peak-to-average power ratio. Here, we consider CAP modulation where matched filtering and equalization at the receiver are performed in the frequency domain, resulting in reduced system complexity. Through numerical results we investigate the performance of this transmission scheme and, in particular, study the impact of the roll-off factor and the length of the pulse shaping filters.","PeriodicalId":247164,"journal":{"name":"2015 4th International Workshop on Optical Wireless Communications (IWOW)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114359603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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